Pamsumm User Manual(0)					Pamsumm User Manual(0)



NAME
       pamsumm - Summarize the samples in a Netpbm image arithmetically


SYNOPSIS
       pamsumm	{  -sum	 | -mean | -min | -max } [-normalize] [-brief] [image-
       file]

       All options can be abbreviated to their shortest	 unique	 prefix.   You
       may  use	 two  hyphens instead of one.  You may separate an option name
       and its value with white space instead of an equals sign.


DESCRIPTION
       This program is part of Netpbm(1).

       pamsumm reads a Netpbm image (PNM or PAM) and performs a summary	 func-
       tion  over  all	the  samples  in all the rows, columns, and planes and
       prints the result to Standard Output.

       pamsumm performs the operation on the actual sample values, not on  the
       light  intensities  represented by them in the case that the image is a
       PGM or PPM image or PAM equivalent.  If you want to  do	arithmetic  on
       light  intensities of such a visual image, you can use pnmgamma to con-
       vert it to one with samples proportional to light intensity,  and  then
       use pamsumm on the result.

       If  you	want  to  summarize  by	 column (e.g. add up the columns sepa-
       rately), use pamsummcol.	 If you want to summarize by row, use a combi-
       nation  of pamsummcol and pamflip.  If you want to summarize a particu-
       lar plane, use pamchannel to extract it and then pamsumm.



OPTIONS
       You must specify exactly one of -sum, -mean, -min, or -max.



       -sum

	      This option makes the summary function addition.


       -mean

	      This option makes the summary function arithmetic mean.


       -min

	      This option makes the summary function arithmetic minimum.


       -max

	      This option makes the summary function arithmetic maximum.


       -normalize

	      This option causes each sample to be normalized to a fraction
		   (in the range 0..1) so the result  is  independent  of  the
	      image's
		   maxval.  E.g. if you request the mean of an image which has
	      maxval
		   200 and all the samples have value 50,  pamsumm  will  give
	      you
		   50 as an answer.  But pamsumm -normalize will give you .25.

	      If  instead  you want a result that is independent of maxval but
	      still
		   in integers, you can use pamdepth to convert the  input  to
	      some
		   standard  maxval  and  not use -normalize.  For example, if
	      you want
		   the mean intensity of a PPM image, on a scale of 0  to  99,
	      do

		  pamdepth 99 myimage.ppm | pamsumm -mean

	      This option was new in Netpbm 10.22 (April 2004)


       -brief

	      This option causes pamsumm to display the answer as a bare
		   number, rather than in a complete sentence.

	      This option was new in Netpbm 10.22 (April 2004)




SEE ALSO
       pamsumm(1), pam(1),


HISTORY
       pamsumm was added to Netpbm in Release 10.21 (March 2004).



netpbm documentation	       07 February 2004		Pamsumm User Manual(0)